Cancer clinical trials and protocol medicine is the approach considered optimal for assuring state-of-the-art treatment and maximizing clinical outcomes. Inadequate patient enrollment is a major impediment to the successful completion of cancer clinical trials and, thus, to the assurance of optimal care. The purpose of the proposed pilot study is to determine the extent to which community oncologists' perceptions of the attributes or characteristics, of clinical trial protocols influence their patient enrollment decisions. An expert panel of cancer specialists will assist in the development of a survey instrument to rate the characteristics of cancer clinical trial protocol. The instrument will be used in a survey of a sample of community oncologists participating in the National Cancer Institute's Community Clinical Oncology Program (CCOP). Twenty breast cancer treatment protocols and twenty cancer control protocols will be selected for review and each oncologist will be asked to use the instrument developed by the expert panel to rate one of each type of protocol. The also will be asked to complete a brief questionnaire regarding their professional background and current practice. The protocol ratings will be examined in relation to the oncologists' actual patient enrollment, controlling and physician and organizational characteristics, in order to determine the extent to which perceived protocol attributes influence enrollment decisions. Information on the number of patients enrolled by each physician on specific protocols is available from the CCOP Evaluation project as is information on the characteristics of each of the local CCOPs with which the oncologists are affiliated.